GameObject.Find("object name") never returns null. Even if object doesn't exist!

Okay, this is very strange… I am using GameObject.Find() in editor(not runtime) and whenever I call it - it returns object, even if it doesn’t exist.

GameObject checkTile = GameObject.Find(tileMap.name + "/Tiles/tile "+ brushPosX + "x" + brushPosY);
		if (checkTile !=null)
		{
			Debug.Log(checkTile);
		}

And console shows: “tile 1x4” or “tile 33x76” or tile “4x15”, etc. But there are no such objects!

I also tried this:

if (GameObject.Find(tileMap.name + "/Tiles/tile "+ brushPosX + "x" + brushPosY))
{
	GameObject checkTile = GameObject.Find(tileMap.name + "/Tiles/tile "+ brushPosX + "x" + brushPosY);

	if (checkTile !=null)
	{
		Debug.Log(checkTile);
	}
}

Stupid me. The way my editor works is when left mouse button is held down a tile is drawn and when shift and mouse button is held down - the tile gets removed.
When I was painting tiles I used this condition in OnSceneGUI():

if (curE.type == EventType.MouseDrag && curE.button == 0 ||
	curE.type == EventType.MouseDown && curE.button == 0)	
	{
		if (toolIndex == 0)
		{
			if (tileMap.floorSet != null) DrawAutoTile();
		} else if (toolIndex == 1)
		{
			//... irrelevant
		}
	}

So basically what I did wrong is I allowed painting tiles even when shift key was down. And this fixed the problem:

Event curE = Event.current;
if (curE.shift) shiftDown = true;
else shiftDown = false;

if (curE.type == EventType.MouseDrag && curE.button == 0 && !shiftDown||
	curE.type == EventType.MouseDown && curE.button == 0 && !shiftDown)
{
	if (toolIndex == 0)
	{
		if (tileMap.floorSet != null) DrawAutoTile();
	} else if (toolIndex == 1)
	{
		// ... Irrelevant
	}
}

Thanks again Le Pampelmuse for your support!